333 



base of the lowest bed of grey sandstone in the Boss Point 

 formation. These overlying Boss Point beds are charac- 

 terized by the presence of grey sandstone bearing abundant, 

 though frequenth' generically obscure, drift plant debris 

 indicative of Pennsylvanian time, and by the occurrence of 

 basal quartz conglomerates seemingly derived from the 

 erosion of upper beds of the underlying Windsor. The 

 geological history represented by this depositional break 

 must be largely of a speculative nature until further 

 regional data are obtainable. 



It is probable, however, that the Cobequid mountains 

 were established as a region of uplift in early Palaeozoic 

 times, and partook of the erogenic movements of late 

 Silurian and post-Silurian times, which took place generally 

 in western New England, and still later possibly they may 

 have suffered post-Devonian deformations. At least the 

 faunal and structural evidence points to the existence of the 

 Cobequids as highlands or islands in the Mississipian sea. The 

 post-Mississippian orogenic movements were Appalachian 

 in character with the thrust from the south, and highly 

 disturbed the Windsor strata in the basin south of the 

 Cobequids, but seemingly little affected these to the north 

 of the Cobequids. Contemporaneous or later vertical 

 movements then initiated a period of active erosion and the 

 deposition of terrestrial deposits in the form of fluvial flood 

 plains and subaerial delta deposits which were derived in 

 part from the large continuous areas of upland to the south 

 and west, and in part from the forelying Appalachian 

 mountain chains. Of these mountain ridges, the Cobequids 

 were sufffciently developed to delineate the two main 

 Carboniferous basins of Nova Scotia. The southern or 

 deeper basin which lay between the Cobequids and the 

 Southern uplands was an area of estuarine or brackish- 

 water deposition resulting in the Riversdale deposits. In 

 the north the Cumberland and the southern New Bruns- 

 wick basins were seemingly continuous and this area was 

 one of contemporaneous terrestrial fluvial deposition, 

 giving rise to the Boss Point (Millstone Grit) sediments. 



Boss Point Formation — The Boss Point formation 

 continues westward from the Windsor belt for about 5 

 miles (8 km.), and consists primarily of two distinct 

 divisions, a lower prevailingly red division, and an upper 

 predominantly grey division. The lower division contains 

 considerable conglomerate which is characterized by the 



